Introduced in 1947, the Wiener index W (T ) = ∑ {u,v}⊆V (T ) d(u, v) is one of the most thoroughly studied chemical indices. The extremal structures (in particular, trees with various constraints) that maximize or minimize the Wiener index have been extensively investigated. The Harary index H(T ) = ∑ {u,v}⊆V (T ) 1 d(u,v) , introduced in 1993, can be considered as the “reciprocal analogue” of ...

The diffraction by a finite parallel-plate waveguide with four-layer material loading is rigorously analyzed by means of the Wiener-Hopf technique for the H-polarized plane wave incidence. Taking the Fourier transform for the unknown scattered field as well as the Helmholtz equation and applying boundary conditions in the transform domain, the problem is formulated in terms of the simultaneous ...

Whereas there is an exact linear relation between the Wiener indices of kenograms and plerograms of isomeric alkanes, the respective terminal Wiener indices exhibit a completely different behavior: Correlation between terminal Wiener indices of kenograms and plerograms is absent, but other regularities can be envisaged. In this article, we analyze the basic properties of terminal Wiener indices...

Space-time variational formulations and adaptive Wiener–Hermite polynomial chaos Galerkin discretizations of Kolmogorov equations in infinite dimensions, such as Fokker–Planck andOrnstein–Uhlenbeck equations for functions defined on an infinite-dimensional separable Hilbert space H , are developed. The wellposedness of these equations in the Hilbert space L2(H, μ) of functions on the infinite-d...

The most important initiator of cybernetics was Norbert Wiener (l894–1964) with his book “Cybernetics or Control and Communication in the Animal and the Machine”. The contribution of Warren S. McCulloch (1898–1969) may be compared to that of Wiener. Cybernetics has also had precursors such as A. M. Ampère who introduced the word cybernétique as well as B. Trentowski who did the same in Polish. ...

A plane sound wave is incident at an angle h upon an infinite array of rigid plates, equally spaced and lying along the yaxis, where (x, y) are two-dimensional Cartesian coordinates. The boundary value problem is formulated into a matrix Wiener–Hopf equation whose kernel is, when the plates and interstices are of equal length, decomposable into two factors which commute and have algebraic behav...

Abstract. In this paper Reverse Wiener index, Reverse Detour Wiener index, Reverse Circular Wiener index Reverse Harary index, Reverse Detour Harary index, Reverse Circular Harary index, Reverse Reciprocal Wiener index, Reverse Detour Reciprocal Wiener index, Reverse Circular Reciprocal Wiener index, Reverse Hyper Wiener index, Reverse, Detour Hyper Wiener index, Reverse Circular Hyper Wiener i...

In this paper we present a simple closed-form solution to the Wiener–Hammerstein (W–H) identification problem. The identification process occurs in the log-frequency domain where magnitudes and phases are separable. We show that the theoretically optimal W–H identification is unique up to an amplitude, phase and delay ambiguity, and that the nonlinearity enables the separate identification of t...

the wiener index is a graph invariant that has found extensive application in chemistry. inaddition to that a generating function, which was called the wiener polynomial, who’sderivate is a q-analog of the wiener index was defined. in an article, sagan, yeh and zhang in[the wiener polynomial of a graph, int. j. quantun chem., 60 (1996), 959969] attainedwhat graph operations do to the wiener po...

In this paper the Wiener and hyper Wiener index of two kinds of dendrimer graphs are determined. Using the Wiener index formula, the Szeged, Schultz, PI and Gutman indices of these graphs are also determined.